What’s an expanded valence shell?
An expanded valence shell is where more than eight of an atom’s electrons participate in covalent bonding. Generally not more than sixteen electrons per atom participate in covalent bonding. Finally, note that an expanded valence shell is also called an expanded octet.
Can Carbon expand its octet?
Octet rule: The concept that compounds containing carbon, nitrogen, oxygen, and fluorine are more stable if these atoms have eight valence electrons. This is an open octet for carbon but not for sulfur, because carbon prefers eight valence electrons whereas sulfur prefers twelve (i.e., sulfur has an expanded octet.)
Can Argon have an expanded octet?
Note that only five elements (C, N, O, F and Ne) always obey the octet rule of having eight valence bonding and lone-pair electrons: all the other elements can have ‘depleted octets ‘ or ‘ expanded octets ‘. Argon compounds have been synthesised and have expanded octets.
Which element can accommodate more than eight electrons in its valence shell?
2) Expanded Octet: Any element in Period 3 and greater can hold more than eight electrons, including phosphorus (10), sulfur (12), chlorine (14), and many others.
Can an atom have more than 8 valence electrons?
octet rule: Atoms lose, gain, or share electrons in order to have a full valence shell of eight electrons. Hydrogen is an exception because it can hold a maximum of two electrons in its valence level.
Why can phosphorus make 5 bonds?
Simple answer: hybridization. Phosphorus only ‘needs’ three more electrons to get a full valence shell of eight, but you’ll notice that it actually has five valence electrons, so in theory all of these could bond. When bonding five times, the s-, p-, and d-orbitals actually fuse to create a hybrid dsp 3 orbital.
Which elements can break the octet rule?
There are three violations to the octet rule: odd- electron molecules, electron -deficient molecules, and expanded valence shell molecules.
Which elements do not follow octet rule?
The two elements that most commonly fail to complete an octet are boron and aluminum; they both readily form compounds in which they have six valence electrons, rather than the usual eight predicted by the octet rule.
What are the octet rule exceptions?
However, there are three general exceptions to the octet rule: Molecules, such as NO, with an odd number of electrons; Molecules in which one or more atoms possess more than eight electrons, such as SF6; and. Molecules such as BCl3, in which one or more atoms possess less than eight electrons.
What is the octet rule for Lewis structures?
Octet rule states that in forming compounds, atoms gain, lose or share electrons to give a stable electron configuration characterized by eight valence electrons. This rule is applied to the main-group elements of the second period. Draw Lewis structures step by step: 1, choose a center atom.
What is Lewis octet rule?
The octet rule refers to the tendency of atoms to prefer to have eight electrons in the valence shell. When atoms have fewer than eight electrons, they tend to react and form more stable compounds. Thus, an atom continues to form bonds until an octet of electrons is made. This is known as octet rule by Lewis.
What is octet rule Class 9?
The octet rule states that an atom tends to have eight electrons in its outermost valence shell by forming covalent bonds through gaining or losing electrons from its outermost shell. Elements that obey octet rules are main group elements which are oxygen, carbon, nitrogen.
How many valence electrons does an atom of oxygen have?
Valence electrons are the electrons in the outermost shell, or energy level, of an atom. For example, oxygen has six valence electrons, two in the 2s subshell and four in the 2p subshell.
Why are there only 8 electrons in the outer shell?
The shells of an atom cannot accommodate more than 8 electrons, even if it has a capacity to accommodate more electrons. This is a very important rule called the Octet rule. According to this rule, atoms gain, loose or share electrons to achieve the stable configuration similar to the nearest noble gas.
Why are atoms stable with 8 valence electrons?
A complete octet is very stable because all orbitals will be full. Atoms with greater stability have less energy, so a reaction that increases the stability of the atoms will release energy in the form of heat or light. A stable arrangement is attended when the atom is surrounded by eight electrons.